PINE PLANTATION: Background

The development of modern silvicultural practices in the 1950's has lead to a dramatic increase in the abundance and distribution of pine plantations over the past 3 decades. Pine plantations are distributed throughout the physiographic region but are most concentrated within the southern portion of the planning unit. Conversion of natural forests to plantations is continuing within the region as second growth forests are reaching harvestable age. Much of this conversion has taken place on the outer Coastal Plain where plantations have replaced natural pine-dominated forests. However, an increasing number of hardwood-dominated forests closer to the fall line are being converted as these forests are harvested. The majority of pine plantations within the region are currently owned and managed by the forest products industry. However, the amount of private and government-owned lands being converted to plantations is increasing.

With the continuing world demand for wood products it seems likely that further conversion will occur within the region.

Within a typical growing cycle, pine plantations proceed through a predictable series of successional stages. After planting, plantations enter a grass stage followed by a shrub/sapling stage. These early successional stages support a diverse community of shrub-dependent bird species. The length of this early stage depends on the time to closure of the pine canopy which in turn depends on factors such as stocking rate and site quality. By year 7 or 8, pine seedlings begin to dominate young plantations, forming a complete canopy by age 9 or 10. Canopy closure results in the decline of understory vegetation. Within the framework of traditional pulp production, canopy closure would be maintained until harvest when the plantation is 20-25 years old. Under such management conditions, bird diversity and density generally declines due to the loss of understory vegetation. More modern techniques of open-canopy management that utilize commercial thinning maintain understory vegetation for a much longer portion of the growing cycle and maintain diverse bird communities that are traditionally associated with natural forests.

As idle grasslands and shrublands have disappeared, early successional pine plantations have become increasingly important to the regional avifauna. Young clearcuts now represent the primary habitat for many shrub-dependent species. Older plantations also provide habitat for a number of forest species.